Introduction/Objective: To describe the changes observed in the practice of breast cancer screening in a Spanish city (Sabadell) after 2 years of a structured screening program activity.

Methods: 1. Analysis of the previous situation, and identification of its weak points and means for overcoming them. 2. Design and execution of a Breast Cancer Screening Program, coordinated by the Technical Screening Office, with the functions of planning, management and evaluation of all aspects of the Program.

Results: Before beginning the program, only 40% of the women from 50 to 64 years old received screening mammograms in a non-systematic fashion, without the results being known or evaluated. After the first round of screening (April 1997 data) in the Sabadell population (women from 50 to 64 years old), close to 68% of the target population participated in the Program, while of the remaining 8% had mammography tests in other public institutions outside of the program and 9% in private centers.

Discussion: An uncoordinated and non-evaluated screening activity can be converted into a much more structured and methodologically solid program with the technical support centralized in a Technical Office that can count on the appropriate human and technical resources. There remain some obstacles to overcome, due to the difficulties caused by insufficient acceptance from all agents involved in the application of the health plans and guidelines defined by external entities.